When people show you who they are believe them

I saw that quote from the extremely wise woman, Dr. Maya Angelou. It says a lot. And not just in regards to men women relations, it means the same for your friends, whether they are men, women. I don't understand it when you are in a relationship, whatever it may be, and one person changes or maybe both people change. So then you wait for them to change back to the person they were. Sometimes it happens, sometimes it doesn't. I want for all men, women to know that quote. I believe it can help.